1. Department of Endocrinology, Imperial College Healthcare NHS Trust, London, UK
2. Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
3. Nightingale-Saunders Clinical Trials and Epidemiology Unit, King’s College London, London, UK
4. Department of Clinical Biochemistry, Northwest London Pathology, London, UK